Fig. 6.3. Kidney transplant in right iliac fossa with anterior ureteroneocystostomy.

peritoneum is mobilized medial and cephalad to expose the underlying retroperitoneal iliac vessels. Often at this point, a mechanical retractor is utilized to improve exposure. The iliac artery and vein are dissected free from the surrounding soft tissues with suture ligation and division of the overlying lymphatics. This is important to minimize occurrence of a posttransplant lymphocele.

There are several alternatives for the vascularization of the renal allograft. Patients that are uremic typically do not require systemic heparinization for the vascular anastomosis. However, preuremic patients should be heparinized. Commonly, the external iliac artery and vein are utilized. There are situations that may require suture ligation and division of the hypogastric veins to mobilize the external iliac vein laterally to improve its position and to optimize the alignment of the kidney allograft. The common iliac artery may be important to use if there is atherosclerotic disease or concern about the perfusion pressure in the extra iliac artery. The internal iliac artery can be used for an end-to-end anastomosis in living donor kidneys or in kidneys that have multiple arteries. Another consideration that is used to determine the location of the arterial anastomosis is how the lie of the kidney in the iliac fossa will be affected by the relationship of its lower pole to the anteriorly rising psoas muscle.

The sutures used for anastomosis in adult kidney transplants are typically 5-0 monofilament for the vein, and 6-0 monofilament for the artery. If there is a very difficult arterial anastomosis because of intimal abnormalities, interrupted stitches are useful. If hypogastric veins need to be ligated they should be stick tied. The length of the renal artery and vein should be examined and the vein trimmed to an appropriate length relative to the artery, leaving it slightly longer when the iliac vein is medial. On right cadaveric kidneys it is very useful to utilize the inferior vena cava as an extension. There is no demonstrable disadvantage in putting a left kidney on the left side or the right kidney on right side. Placing the contralateral kidney in the iliac fossa does make for a more natural vascular alignment when the vein is mobilized lateral relative to the artery. Also, the ureteral collecting system is relatively anterior to the vessels in the hilum.

After completion of the vascular anastomoses the ureterocystostomy is performed. It is important in males that the ureter be slipped under the cord structures. The ureteral artery needs to be securely ligated. The ureter is then cut and spatulated. There are 3 common methods of ureteral anastomoses. The Ledbetter-Politano procedure requires an open cystotomy and the ureter is tunneled posteriorly near the trigone. The most common approach is the anterior ureteroneocystostomy in which the spatulated ureter is directly sutured to the bladder mucosa, followed by approximation of the muscularis to create a tunnel over the distal 2 cm of the ureter (Fig. 6.4). This approach has been modified as a single stitch procedure, whereby the ureter is invaginated in the bladder with a single stitch, followed by the approximation of the muscular layer to create a tunnel to prevent reflux (Fig. 6.5). In the unusual situation involving a duplicated collecting system, separate ureterocystotomies are performed for each ureter. Alternatively, the tips of the ureters may be fish-mouthed and sewn together creating a single ureteral orifice for anastomosis to the bladder mucosa. In very unusual cases where the bladder can not be used, urinary drainage using an ileal loop is successful. In some centers, ureteral stents are often routinely employed. This may minimize the occurrence or early urine leaks or ureteral stenosis. The ureteral stents are removed approximately 6 weeks posttransplant via flexible cys-toscopy in the outpatient setting.

It is usually not necessary to place a retroperitoneal drain. However, if needed, it is perfectly reasonable to place close suction drainage which is required only for about 24-48 hours. Wound complications can be associated with significant morbidity. Careful closure of the incision that incorporates all layers of the muscle and fascia is important to prevent hernia. Keeping the wound edges moist with

0 0

Post a comment